The length 'x' of a rectangle is decreasing at the rate of 3cm/m and t

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The length 'x' of a rectangle is decreasing at the rate of 3cm/m and the width 'y' is increasing at the rate of 2cm/m.find the rates of change of :
(a) the perimeter (b) the area of the rectangle when X = 8 cm and y = 6 cm.